Getting read/write to protected memory errors crashing using Twain class libraries

Hello,

Thank you for viewing this post. I hope those who read this can help me with a very frustrating problem. We downloaded the Lead Tools Imaging Pro SDK .NET to see if we could implement the twain libraries into our program. Here is the current situation.

We are using a Xerox Document 152 as our scanner. When we try to acquire an image from the Xerox Scanner we call their UI via the Twain specification under Microsoft Vista. We are issuing the DAT_USERINTERFACE, MSG_ENABLEDS command. At that point the twain app crashes due to the twain driver attempting to read or write to protected memory. Has anyone seen this type of behavior before?

Windows Vista SP1.

Thank you for your time.

-Loryn

Loryn,
If you use the standard Twain test utility from the Twain Working Group (Twacker) to set the same capabilities or properties that produce this error, do you set them correctly? Just run the Twacker application and try the following:
- Select (check) the menu "File-->Disable after Acquire".
- Uncheck the menu "File-->ShowUI".
- Select the menu "File-->Select Source", and then select your scanner driver from the list.
- Select the menu "File -->Acquire".

Just try to get and set the same capability or property using the same twain driver that you use using the Twacker application. If the Twacker utility does not succeed, nothing will.
You can get 'Twacker' from here: http://www.twain.org/devfiles/twack.zip.